Source code for quixote.build.debconf

"""
Module providing helpers to deal with the debconf database, which is used to configure Debian packages.
"""

import quixote.build.shell as shell
from typing import Union, List


class _DebconfTypeMeta(type):
    def __new__(mcs, name, underlying_type_hint, formatter):
        def init(self, value: underlying_type_hint):
            """
            :param value:           the value to use for the answer
            """
            self.value = value

        wrapper = type(name, (object,), {})
        wrapper.__doc__ = f"Class representing a debconf answer of type '{name}'"
        wrapper.__init__ = init
        wrapper.__str__ = formatter
        return wrapper


Select = _DebconfTypeMeta("Select", str, lambda self: f"select {self.value}")
MultiSelect = _DebconfTypeMeta("MultiSelect", List[str], lambda self: f"multiselect {', '.join(self.value)}")
String = _DebconfTypeMeta("String", str, lambda self: f"string {self.value}")
Boolean = _DebconfTypeMeta("Boolean", bool, lambda self: f"boolean {str(self.value).lower()}")
Note = _DebconfTypeMeta("Note", str, lambda self: f"note {self.value}")
Text = _DebconfTypeMeta("Text", str, lambda self: f"text {self.value}")
Password = _DebconfTypeMeta("Password", str, lambda self: f"password {self.value}")


def set_selections(
        package: str,
        question: str,
        value: Union[Select, MultiSelect, String, Boolean, Note, Text, Password]
):
    """
    Insert an answer for a given question of a given package into the debconf database (see debconf-set-selections(1))

    :param package:         the package owning the question
    :param question:        the name of the question
    :param value:           the value to use as answer for this question
    """
    return shell.command(f"echo {package} {question} {value} | debconf-set-selections")


def reset(package: str, question: str):
    """
    Reset answers for a given question of a given package in the debconf database

    :param package:         the package owning the question
    :param question:        the name of the question
    """
    return shell.command(f"echo RESET {question} | debconf-communicate {package}")


def unregister(package: str, question: str):
    """
    Unregister a given question of a given package in the debconf database

    :param package:         the package owning the question
    :param question:        the name of the question
    """
    return shell.command(f"echo UNREGISTER {question} | debconf-communicate {package}")


def purge(package: str):
    """
    Purge all the answers for questions of a given package in the debconf database

    :param package:         the package whose questions to purge
    """
    return shell.command(f"echo PURGE | debconf-communicate {package}")